### Target language

Translate to Simplified Chinese (简体中文).

Language code: zh.

### Grammar and tone

1) Use clear, concise technical Chinese consistent with existing docs.
2) Address the reader naturally (commonly using “你/你的”).

### Headings

1) Follow existing Simplified Chinese heading style (short and descriptive).
2) Do not add trailing punctuation to headings.

        }
    }
)


class User(BaseModel):
    username: str


# Here we use string annotations to test them
def get_current_user(oauth_header: "str" = Security(reusable_oauth2)):
    user = User(username=oauth_header)
    return user


@app.post("/login")
# Here we use string annotations to test them
def login(form_data: "OAuth2PasswordRequestFormStrict" = Depends()):
    return form_data

Keep in mind that dataclasses can't do everything Pydantic models can do.

So, you might still need to use Pydantic models.

But if you have a bunch of dataclasses laying around, this is a nice trick to use them to power a web API using FastAPI. 🤓

///

## Dataclasses in `response_model` { #dataclasses-in-response-model }

You can also use `dataclasses` in the `response_model` parameter:

        Doc(
            """
            Pydantic's `by_alias` parameter, passed to Pydantic models to define if
            the output should use the alias names (when provided) or the Python
            attribute names. In an API, if you set an alias, it's probably because you
            want to use it in the result, so you probably want to leave this set to
            `True`.
            """
        ),
    ] = True,

@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

<details markdown="1">
<summary>Or use <code>async def</code>...</summary>

If your code uses `async` / `await`, use `async def`:

```Python hl_lines="9  14"
from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/")

        max_length: Optional[int] = None,
        pattern: Optional[str] = None,
        regex: Annotated[
            Optional[str],
            deprecated(
                "Deprecated in FastAPI 0.100.0 and Pydantic v2, use `pattern` instead."
            ),
        ] = None,
        discriminator: Union[str, None] = None,
        strict: Union[bool, None] = _Unset,
        multiple_of: Union[float, None] = _Unset,

of English terms and their preferred German translations, separated by a colon («:»). Use these translations, do not use your own. If an existing translation does not use these terms, update it to use them. In the below list, a term or a translation may be followed by an explanation in brackets, which explains when to translate the term this way. If a translation is preceded by «NOT», then that means: do NOT use this translation for this term. English nouns, starting with the word «the», have the...

/// tip

**GraphQL** solves some very specific use cases.

It has **advantages** and **disadvantages** when compared to common **web APIs**.

Make sure you evaluate if the **benefits** for your use case compensate the **drawbacks**. 🤓

///

## GraphQL Libraries { #graphql-libraries }

Here are some of the **GraphQL** libraries that have **ASGI** support. You could use them with **FastAPI**:

        Doc(
            """
            An alternative name for the parameter field.

            This will be used to extract the data and for the generated OpenAPI.
            It is particularly useful when you can't use the name you want because it
            is a Python reserved keyword or similar.
            """
        ),
    ] = None,
    alias_priority: Annotated[
        Union[int, None],
        Doc(
            """

class UploadFile(StarletteUploadFile):
    """
    A file uploaded in a request.

    Define it as a *path operation function* (or dependency) parameter.

    If you are using a regular `def` function, you can use the `upload_file.file`
    attribute to access the raw standard Python file (blocking, not async), useful and
    needed for non-async code.

    Read more about it in the